一步一步完成SSM框架整合(Spring+Spring MVC + Mybatis)
新建maven工程
eclipse中选择new Maven Project项,制定archetype为webapp,填写好groupId之类的,然后finish,这时可能工程有一些错误,通过修改Java Build Path,修复错误:
然后new一个server,将这个项目添加进去,修改server的context path为“/”,http端口设置为“80”,然后打开浏览器,访问“127.0.0.1”,出现“Hello world”即为成功:
加入Spring
首先在pom.xml文件中dependency节点下添加下列依赖:
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>
版本在properties节点下自己控制,这里只用引入一个spring-context,相关依赖的jar maven会帮我们自动引入,不用重复累赘再写一次。
为了测试spring集成的效果,我们需要一个bean来测试,新建一个User测试类:
package com.cjt.ssm.model;
public class User {
private String name;
private int age;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}
同时在resources目录下新建一个spring的入口配置文件spring.xml:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://www.springframework.org/schema/beans" xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">
<bean id="user" class="com.cjt.ssm.model.User" />
</beans>
然后新建main方法测试类Test,测试spring是否集成成功:
package com.cjt.ssm;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.cjt.ssm.model.User;
public class Test {
public static void main(String[] args) {
ApplicationContext context = new ClassPathXmlApplicationContext("spring.xml");
User user = context.getBean("user", User.class);
System.out.println(user);
}
}
运行Test类,若是spring集成成功,日志台会打印相关spring加载日志,并且user也能够正常获取,打印user:
加入Mybatis
涉及到数据持久化方面,首先得有数据来源,在本地mysql数据库ssm下新建一张user表:
然后随便添加一条记录,{“name”:”ssm”,”age”:18},方便待会测试之用;
然后同样在pom.xml添加MyBatis的依赖:
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>${mybatis.version}</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>${mysql.version}</version>
</dependency>
指定版本为mybatis版本为3.2.0,mysql版本是5.1.33;
在resources目录下新建mybatis.xml,作为mybatis的配置文件:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC" />
<!-- 配置数据库连接信息 -->
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost:3306/ssm" />
<property name="username" value="root" />
<property name="password" value="xxx" />
</dataSource>
</environment>
</environments>
<!-- resource需要写成路径的形式 -->
<mappers>
<!-- <mapper resource="userMapper.xml"/> -->
</mappers>
</configuration>
然后同目录新建测试的userMapper.xml,主要用于编写sql:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<!-- namespace用作标识mapper的唯一,通常包名+文件名 -->
<mapper namespace="user">
<select id="findAll" resultType="com.cjt.ssm.model.User">
select * from user
</select>
</mapper>
记得在上面mybatis.xml配置文件的mappers节点下添加这个作为测试的userMapper,这样mybatis的准备工作也做完了,修改Test内容,验证MyBatis是否正常:
package com.cjt.ssm;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import com.cjt.ssm.model.User;
public class Test {
public static void main(String[] args) throws IOException {
String resource = "mybatis.xml";
InputStream is = Resources.getResourceAsStream(resource);
// build接受不同的参数,可采取其他方法创建SqlSessionFactory
SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(is);
SqlSession session = sessionFactory.openSession();
String statement = "user.findAll";
// session拥有多个方法,可以自行研究
List<User> users = session.selectList(statement);
for (User user : users) {
System.out.println(user);
}
}
}
修改User类增加toString()方法,运行程序,若是能正常打印我们user表中的数据,则MyBatis配置成功:
整合Spring与MyBatis
首先新建一个dao包,在下面编写User对应的借口UserDao:
package com.cjt.ssm.dao;
import java.util.List;
import com.cjt.ssm.model.User;
public interface UserDao {
List<User> findAll();
}
然后修改spring.xml配置文件,将数据库配置和dao所对应的bean都添加进去:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://www.springframework.org/schema/beans" xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close">
<property name="driverClassName">
<value>com.mysql.jdbc.Driver</value>
</property>
<property name="username">
<value>root</value>
</property>
<property name="password">
<value>Cjt00382114.</value>
</property>
<property name="url">
<value>jdbc:mysql://localhost:3306/ssm</value>
</property>
</bean>
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="configLocation" value="classpath:mybatis.xml" />
</bean>
<!-- DAO接口所在包名,Spring会自动查找其下的类(不用写注解) -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.cjt.ssm.dao" />
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property>
</bean>
</beans>
记得修改userMapper.xml的namespace为该Dao的全路径,这样保证了spring绑定的bean能够执行对应的sql语句,然后去掉mybatis.xml配置文件中的数据源配置节点environments ;
这一步就要添整合相关的依赖jar包了:
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>${commons-dbcp.version}</version>
</dependency>
<dependency>
<groupId>commons-dbcp</groupId>
<artifactId>commons-dbcp</artifactId>
<version>${commons-dbcp.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>${spring.version}</version>
</dependency>
修改Test文件,准备测试:
package com.cjt.ssm;
import java.io.IOException;
import java.util.List;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.cjt.ssm.dao.UserDao;
import com.cjt.ssm.model.User;
public class Test {
public static void main(String[] args) throws IOException {
ApplicationContext ctx = new ClassPathXmlApplicationContext("spring.xml");
UserDao userDao = ctx.getBean("userDao", UserDao.class);
List<User> users = userDao.findAll();
for (User user : users) {
System.out.println(user);
}
}
}
观察控制台输出,正常输出user表中的数据则说明spring与mybatis集成成功:
集成Spring MVC
首先引入Spring MVC所需要的jar包:
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-mapper-asl</artifactId>
<version>${jackson.version}</version>
</dependency>
修改spring.xml,添加springmvc相关配置:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://www.springframework.org/schema/beans"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.2.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd">
<mvc:annotation-driven />
<context:component-scan base-package="com.cjt.ssm" />
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix">
<value>/</value>
</property>
<property name="suffix">
<value>.jsp</value>
</property>
</bean>
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close">
<property name="driverClassName">
<value>com.mysql.jdbc.Driver</value>
</property>
<property name="username">
<value>root</value>
</property>
<property name="password">
<value>Cjt00382114.</value>
</property>
<property name="url">
<value>jdbc:mysql://localhost:3306/ssm</value>
</property>
</bean>
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="configLocation" value="classpath:mybatis.xml" />
</bean>
<!-- DAO接口所在包名,Spring会自动查找其下的类(不用写注解) -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.cjt.ssm.dao" />
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property>
</bean>
</beans>
然后修改web.xml,配置springmvc servlet分发器,并设置request/response的编码格式:
<!DOCTYPE web-app PUBLIC
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd" >
<web-app>
<!-- 编码过滤器 -->
<filter>
<filter-name>encodingFilter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
<init-param>
<param-name>forceEncoding</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>encodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<servlet>
<servlet-name>springmvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>springmvc</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>
新建controller,作为springmvc的测试之用:
package com.cjt.ssm.controller;
import java.util.List;
import javax.annotation.Resource;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import com.cjt.ssm.dao.UserDao;
import com.cjt.ssm.model.User;
@Controller
@RequestMapping(value="/")
public class TestController {
@Resource
private UserDao userDao;
@RequestMapping(value="/test")
@ResponseBody
public List<User> test(){
List<User> users = userDao.findAll();
return users;
}
}
此时就可以启动server,测试了:
此时,还没算作大功告成。。。
解决乱码
乱码的问题,归根结底就是编码不一致导致的。例如,你的文件是utf-8的,你却硬要用gbk的编码方式展示,那么就会显示一长串的乱码。既然这样,那么简单来说,解决办法即为统一编码。为了字符编码兼容,统一设置为“UTF-8”。
首先设置filter过滤器,设置request和response的编码方式,在web.xml中添加过滤器:
<!-- 编码过滤器 -->
<filter>
<filter-name>encodingFilter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
<init-param>
<param-name>forceEncoding</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>encodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
这个对应解决post表单的参数后天接受时,和response往页面输出内容时出现的乱码情况,但记得使用response的时候设置response.setContentType("text/html;charset=UTF-8")
;
使用jsp页面渲染的要注意头部添加<%@ page contentType="text/html; charset=UTF-8" %>
,并且同时设置当前html<meta charset="UTF-8">
,其他页面渲染(freemaker、vm等)自行研究配置,这里不深入讨论。这适用于解决一些原本存在页面中的中文乱码,即controller返回的页面原本的中文内容乱码。
springmvc、tomcat、eclipse默认都是ISO-8859-1
,所以都需要手动设置编码为UTF-8
。
因此,若是controller注解了@Responsebody
直接返回的String内容,没有经过response输出,这种也会乱码,所以还要修改spring.xml,配置springmvc的编码,将<mvc:annotation-driven />
修改为:
<mvc:annotation-driven>
<!-- 消息转换器 -->
<mvc:message-converters register-defaults="true">
<bean class="org.springframework.http.converter.StringHttpMessageConverter">
<property name="supportedMediaTypes" value="text/html;charset=UTF-8"/>
</bean>
</mvc:message-converters>
</mvc:annotation-driven>
到这里可以算作,SSM框架集成成功!!
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